While the manhunt is in progress

Chapter 400 Narrowing the Scope
"In fact, after the incident, many problems in the school were exposed." Pang Yi said helplessly: "Among them are not only the logistics director and his brother-in-law, but also the canteen supervisor, teaching director, head teacher, security department, etc. "

"After our investigation, although they have been cleared of the suspicion of poisoning, many other problems have also been noticed by everyone, so they were all punished or arrested later."

Song He shook his head and said, "Your investigation has basically wiped out groups other than students, but you haven't found any suspects. Naturally, these people have been focused on."

"However, although only one-tenth of the investigation has been carried out, it has indeed narrowed the scope of the investigation."

Pang Yi smiled awkwardly, not knowing whether Song He was praising or complaining.

"Come on, let's simulate the route of milk." Song He said while calculating: "Generally, there are two to three time points in a day when a farm collects milk, [-]-hour system and [-]-hour system."

"In order to cooperate with the school's schedule, the collection time of this brother-in-law's farm is [-]:[-] am and [-]:[-] pm. The students were poisoned in the morning, that is, the batch collected in the early morning was poisoned."

"You have investigated the period from the completion of the collection to the delivery to the school cafeteria, and ruled out the possibility of poisoning. Then the only chance of poisoning is to mix and cook it, divide it, and send it to the classroom for the students It's time to drink."

"At that time, the packing was during the second class in the morning, and the packing equipment was a large insulated bucket with a faucet for the cafeteria. After class, the students in charge of each class would take advantage of the time between classes to go to the cafeteria to carry the milk of their class. return."

"So from the moment the packaging starts, what people or things will these extra meals that will enter the students' stomachs come into contact with?"

Everyone thought for a moment, and Zhou Kai was the first to speak: "The canteen staff in charge of dispensing, they are the first batch of suspects who can do precise poisoning."

Wu Xuerui continued: "The thermos, so the staff responsible for cleaning the thermos are also suspect."

Ma Xue thought for a while and said: "Students who are in charge of the day will definitely come into contact with them, and they may also have contact with the students on duty from more than one class. After all, counting the exercises between classes, the rest time is nearly half an hour."

"And the students on duty don't have to do exercises, so the students on duty in other classes have full time to inject poison."

Lin Hui glanced at Gu Xiaole, and signaled to give her the opportunity to speak, but Gu Xiaole shook his head slightly, winked at Lin Hui and said: "What I thought of has already been said!"

Lin Hui was helpless, so he had no choice but to say: "Anyone you meet on the way to bring the thermos back to the classroom, and the first person to unscrew the tap of the thermos, can't rule out the teacher's suspicion."

"So the confessions of the students on duty at that time are very important." Song He nodded and took out two transcripts: "The two students who were responsible for moving the thermos said that before they arrived in the cafeteria, many thermos had been taken by the students in each class. The student on duty has moved away."

"And the signatures on the extra meal receipt form do prove that what they said is true. In other words, the students who moved the thermos bucket before them are all suspects."

Song He pointed to another place in the transcript and said: "On the way back to the classroom, I met two teachers, but neither of these two teachers touched the thermos."

"After putting the incubator in the classroom, the two students on duty went to the bathroom to drain water, then went to buy snacks, and then went back to the classroom with the students who had finished their exercises. During this period, the incubator was left unsupervised."

"So in theory anyone has the opportunity to poison, but considering the actual situation, except for most of the teachers and students who are out of the drill, the suspects can be ruled out, and the students on duty in the rest of the class, the students who are absent from the drill, and some teachers and students are all capable of committing the crime. time."

Zhou Kai shook his head and said, "The number of suspects to be investigated is still too large. Can you narrow down the scope?"

"Yes." Song Hedao said: "According to the test results of the hospital, the toxin content in the poisoned children at that time was very close. Considering the special water cups issued by the school for extra meals, it can be basically concluded that the poison has been evenly dissolved in the water when drinking. Inside the thermos."

"However, it takes time to dissolve evenly after poisoning, and the rat poison chosen by the poisoner is a very common street food, and the dissolution speed is not fast, unless it is stirred quickly with a tool of sufficient length after poisoning."

"However, once stirred, no matter what the tool is, it will inevitably leave traces and drug residues, but there are no relevant traces and tools in the school, which means that the poisoner evacuated immediately after committing the crime."

Wu Xuerui understood: "So you want to say that except for the two students on duty, the students in Class [-], Grade [-] are basically not suspected?"

"I think so." Song He nodded, shrugged and said, "From the time point of view, they don't have enough time to commit crimes, and Team Pang has also investigated their entire class. They are all ordinary children and have no abnormal behavior or crimes. motivation."

"In addition, I also want to find out when the medicine was put into the insulation bucket, which requires us to figure out the exact time of poisoning. So I want Captain Pang to help get some milk and rat poison. I don't know if it is convenient to put it in. ?”

Pang Yi didn't intervene much, seeing Song He take the initiative to mention it to him, he immediately agreed: "Don't worry, I'll get it soon."

As he spoke, he made a phone call, and after a while, several police officers came to the school with the things Song He needed.

Soon, everyone began to experiment. First, the milk was heated and poured into the insulation bucket, and then the medicine was put in.

A few minutes later, the medicine dissolved, and Song He checked the time: "If you count the time, the latest is not long after the students on duty left the classroom. Of course, it is also possible that they were drugged before they went to the cafeteria."

Pang Yi suddenly shook his head and said, "It wasn't that time. We have investigated all the students on the extra meal claim form, and there is no suspicious person."

"Not necessarily." Song He waved his hand to retort: ​​"Is it possible that someone pretended to be a student on duty to get the extra meal, and then left after secretly poisoning, without receiving the extra meal and registering?"

Pang Yi was taken aback, then sighed: "It is indeed possible."

Seeing this, Song He comforted: "Captain Pang, I'm sorry, I just habitually want to consider several possibilities."

Pang Yi smiled: "It's understandable, it's all for the case."

In this way, everyone kept discussing, and finally narrowed down the range of suspects to nowhere at noon, but even so, more than 100 students were still included in the range of suspects.

Song He looked at the list, looked at Wu Xuerui apologetically, and said softly: "Xiaoxue, I'm sorry, this is a list that has taken almost all factors into consideration."

"What are you doing, bring it to my old lady!" Wu Xuerui readily took the list, and quickly logged into the system to start searching.

At this time, everyone was idle, and Zhou Kai suddenly saw Song He lost in thought, and couldn't help asking: "What did you think of?"

Song He frowned and said, "I don't know what the poisoner's motive is now? Is he targeting one person? Or several people? Or is it everyone in Class [-], Year [-]?"

"Or is he just throwing poison randomly, and it doesn't matter who he hurts?"

(End of this chapter)